Neuroethics is most commonly understood to be the bioethics subcategory concerned with neuroscience and neurotechnology. However, some philosophers, ethicists, and scientists have increasingly stressed the possibility that neuroscience can shed light on wider ethical questions.

Rees and Rose (as cited in "References" on page 9) claim neuroethics is a neologism that emerged only at the beginning of the 21st century, largely through the work of ethicists and philosophers. They state that neuroethics addresses concerns about the effects neuroscience and neurotechnology will have on other aspects of human life: namely "personal responsibility", law, and justice. Further, they claim that neuroethical problems will become real by the 2020s.

However, Dartmouth College Center for Cognitive Neuroscience Director Michael Gazzaniga argues that definitions such as Safire's are inadequate, since knowledge of brain mechanisms can illuminate a broad range of ethical questions. Gazzaniga states that "neuroethics is more than just bioethics for the brain." In his book The Ethical Brain , he defines the field as: "the examination of how we want to deal with the social issues of disaease, normality, mortality, lifestyle, and the philosophy of living informed by our understanding of underlying brain mechanisms" (Gazzaniga's emphasis).

Gazzaniga puts this view succinctly by stating that "It is—or should be—an effort to come up with a brain-based philosophy of life."

The years 2002 and 2003 saw significant development of neuroethics as a subject of wide discussion. Judy Illes of the Stanford Center for Biomedical Ethics claimed the neuroethical discipline "emerged formally" sometime in 2002 or 2003, though she actually dates its development to 1989. Regardless of whether this is true, it is undeniable that neuroethics rose to new relevance during the early 21st century. Indeed, four major neuroethics conferences occurred in the year 2002 alone: